Hot-gas valve



y 6, 5 F. M. M DOLIGALL 2,596,036

HOT-GAS VALVE Filed May 12, 1945 2 SHEETS-SHEET 2 HT TOEh/E V6.

Patented May 6, 1952 HOT-GAS VALVE Franklin M. MacDougall, Kirkwood, Mo., assignor to Alco Valve Company, University City, Mo., a corporation of Missouri Application May 12, 1945, Serial No. 593,437

15 Claims. 1

The present invention relates to a hotgas valve. More particularly, it consists of a refrigerant distributor for liquid and for hot gas. In the mechanism, there is a distributor for refrigerant with a supplemental valve, operated upon admission of hot gas thereto for distributing it to the refrigeration coils, particularly for the defrosting thereof.

It is an object of the invention to provide a refrigerant distributor with means for the distribution of the refrigerant, together with means for selectively admitting hot gas to the refrigerant passages for the purpose of defrosting the evaporator coils. More particularly, it is an object of the invention to provide the foregoing with a normally closed valve cutting off the hot gas supply and which valve is automatically opened upon the admission of hot gas to'one side thereof.

A further object is to provide the foregoing combination with an expansion valve.

A further object is to provide the foregoing combination together with a thermal valve that is connectable with the refrigerant distribution passages, together with a supplemental hot gas valve as aforesaid.

In the drawings:

Fig. 1 is a more or less diagrammatic view of a refrigerationsystem into which the present invention has been added;

Fig. 2 is a medial transverse section through the distributor itself, showing a manual expansion valve and an automatically operatedsteam valve;

Fig. 3 is a view of thetwo valves of Fig. 1, but taken at 90 to the section of Fig. 2, on the line 3-3 of that figure;

Fig. 4 is a transverse section through thedistributor at the distribution passages, taken on the line 4-4 of Fig. 2;

Fig. 5 is a transverse section through the hot gas inlet, taken on the line 5-5 of Fig. 2; and

Fig. 6 is a view taken on the liquid bypass inlet at the line 66 of Fig. 2.

InFig. 1, a compressor is shown at I0. It distributes hot gas under compression into a line I I, which conveys the hot gas via a check valve, .as shown at C, to the condenser and receiver l2. The latter liquefies the gas, and from it the liquid refrigerant is carriedby a line l3 to a valve M, which maybe manually or automatically operated as desired. From the valve l4, the liquid is conveyed to a strainer I5, and thence to a thermal expansion valve I6 of a type known in the art. This thermal valve controls the exc1. ea-s) pansion of the liquid under reduced pressure to a distributor generally indicated at IT. In the present disclosure, the distributor is shown as a multi-outlet distributor and it evenly divides the refrigerant to a plurality of coils within an evaporator IB. From the evaporator, a suction line [9 carries the gases back to the compressor [0.

From the hot gas line I l .a bypass hot gas line 20 leads through a manual or automatic valve 2 I. and, by a continuation 22 of the line 20, into the distributor ll, as will appear in more detail hereafter. I

Similarly, a liquid bypass line 23 leads from the line 13 through a manual or automatic valve 24,whence a continuation line 25 also leads into the distributor H in a manner to be described in more detail hereafter.

The thermal valve is provided with a bulb 28 connected by a capillary 29 to operate the expansion valve within the thermal valve mechanism in response to outlet temperature. The thermal valve is also provided with an equalizer line 30 so that it will maintain constant superheat in the mannerknown in the art.

' The distributor I1 is shown in greater detail in Figs. 2 to 6. It has a body member 33 with a projection 34 at its left end for connection with the thermal valve IS. The body member 33 has an axial bore 35 running completely through it from end to end. This bore has an enlarged central portion forming a Well 36 which receives valves, as will appear, and opens out to the right end of the main body portion 33. A cap member 3'! is screwed onto the right end of the body member 33, as shown. The cap has a projection 38 on its outer side, and a bore 39, coaxial with the bore 34, extending through the main part of the cap and the projection 38.

The well 36 receives a distributor head insert 40 which has an inlet opening 4| that is coaxial with the bore 35. The port 4| enlarges into a cylindrical bore 42 for receiving a valve, as is shown, the shoulder between them forming a, valve seat 43. The insert 40 has a distributor outlet'head 44 of an outside diameter to fit closely within the well 36 within the body portion 33. To the right of the head 44, the insert 40 has a reduced diameter, forming a sleeve 45 at its right end. The extreme right end of the sleeve 45 is engaged in a cut-out within the inner surface of the housing cap 31, so that the entire J left end.

The head 44 of the insert 40 is provided with a plurality of radially extending relatively small refrigerant passages 49. These passages are intersected by transverse ports 50 that open out of the right end of the enlarged head 44. Radially outward from these transverse ports 50, the several radial passages 49 are continued by somewhat enlarged passage sections 5|. These latter are adapted to register with a plurality of larger radial passages 52 within the body portion 33. The passages 52, in turn, are adapted to be connected by pipes 53, which themselves are some- What enlarged. There is a pipe 53 for each of the coils within the evaporator.

The valve seat 43 is adapted to be engaged by a valve 54 which is axially reciprocable in the bore 42 of the sleeve 45. It is in the form of a conical valve and has around it a hexagonal flange 55 to give it bearing within the port and yet to permit the flow of gases therearound. The valve 54 has a threaded stem 56 threadedly mounted within the bore 3d of the cap 3'! of the main housing member. The stem 55 passes through a packing gland 5'! which is acted upon by a threaded compression plug 58. The outer end of the valve stem 55 may be engaged by a wrench for operating the valve toward or from its valve seat. A dust and protective cap 59 is threaded over the projection of the cap, providing positive sealing against any leakage past the packing gland 5'! and protecting the valve members against inadvertent movement.

The previously mentioned hot gas line 22 enters the valve body 33 at a point to the right of the outlets 49 (Fig. 2). It thereby communicates into the enlarged passage 36 of the valve body adjacent the sleeve portion 45 of the insert 40. On the outer surface of this sleeve portion, a valve 51] is adapted to slide. This valve, referring particularly to Figs. 2 and 3, has a central portion 6!, a port closing flange 62, and a right hand piston-like flange 63. Beyond the flange 63, there is a continuation 64 of the portion 6|.

, This continuation is provided with a plurality of ports 65 that are adapted to register with the corresponding ports 66 within the sleeve portion 45. A coil spring 61 of predetermined force acts against the flange 63 and against the inner end of the cap member 31'. The liquid bypass line 25 enters by a port 68 within the housing 33 to the enlarged portion 36 of the bore'for registry with the ports 66 in the sleeve when the valve member 6| is in its leftward position, as shown in the drawings. A peripheral depression 70 around the inner surface of the valve 60 insures free passage to gas from the ports 66 to the ports 65 whatever the angular disposition of the valve 66 about the sleeve 45.

Operation For normal refrigeration cycle, the valve I4. is open, the valve 24 is closed, the valve 2| is closed, and the manual valve 54 on the distributor is open. The compressor 19 is caused to operate in response to a conventionally located thermostat, or the like. The thermal valve I6 is opened to a degree regulated by the bulb 28 and the pressure conditions, to maintain a constant superheat at the outlets of the coils of the evaporator I8, all as is known in the art. The course of the refrigerant is from the compressor l 0 through the line H, to the condenser and receiver. Within the line i l, the refrigerant is in a hot gas state. From the condenser l2, the refrigerant passes as a liquid through the liquid line IS, the valve M, the

desired.

strainer 15, to the thermal valve [6. From the thermal valve, it flows into the inlet port 35 of the distributor 33. Therein, with the valve 54 open, the refrigerant passes through the valve seat 43 to the bore 42, and thence out through the various radial distribution passages 49, 5|, 52 and 53, to the several coils of the evaporator. From the evaporator, it is drawn back into the suction line I9 to return to the compressor.

During the foregoing operation, the valve 60 is maintained in a closed position primarily b the spring 61. The gas that passes from the bore 42 through the port 66 and 65 acts upon the right side of the flange 63 with a force greater than that exerted by the gas in the transverse ports 59 against the leftside of the flange 62, and, therefore, exerts a closing force on the valve 60.

When it is desired to bypass the thermal valve for any reason, such as servicing it, the line valve 14 is closed, and the line valve 24 in the liquid bypass line 23 is opened. Also, the manual valve 54 within the distributor is closed. Thereupon, the liquid refrigerant may flow through the bypass line 23, the valve 24, and the line 25, into the distributor casing 33. It enters the port 68 to the right hand side of the flange 63 of the valve 66 where it again urges the slide valve 60 closed. It flows through the radial ports 65 of the slide valve Gil, and thence through the ports 66 of the sleeve 45 into the interior 42 of the sleeve 45. It passes around the hexagonal flange 55 on the valve 54, and then may flow out through the radial distribution passages 49, etc., as it did under the control of the thermal valve.

When it is desired to defrost the evaporating coils, or for an other reason to pass hot gas through the system, the line valves l4 and 24 are closed, and the line valve 2| within the hot gas bypass line 26 is opened. The position of the manual valve 54 is immaterial. This admits hot gas from ahead of the condenser into the distributor body 33 through the line 22. It enters the space between the two flanges 62 and 63 of the valve 66. It will be observed that these two flanges have an area difierential, so that the pressure of the hot gas acts with greater force to the right against the flange 63 than it does to the left against the flange 62. This differential force is sufficient to overcome the spring 66, so that the valve 60 is thereupon moved to the right in Figs. 2 and 3.

When the valve 60 slides to the right as aforesaid, it uncovers the transverse ports 50 within the insert 40, and admits hot gas through the radial ports 49 and their continuations, into the various distribution lines 53. Incidentally, the hot gas flowing through the transverse ports 50 lowers in pressure, so that the gas pressure conveyed back to the right of the flange 63 is always below that acting directly on the left side. In passing through the evaporator coils, the hot gas melts any frost on the outside thereof. Thereupon, it is again drawn back through the suction line to the compressor for recirculation.

It will be seen that this mechanism provides a very convenient arrangement by which the refrigeration system may be operated under the automatically controlled thermal valve or under a manual expansion valve or may be operated with hot gas for defrosting purposes and the like. All of the foregoing may be accomplished by the simple operation of fourvalves, of which the three valves I4, 24 and 2| may be automatic if It also involves the use of a single distributor mechanism.

It will also be observed that the valves are arranged so that there will be no interference from the other portions of the system when any one of the foregoing operations is being performed. The manual valve 54 may be closed to prevent backfiow of the refrigerant or the hot gas into the thermal valve when that valve is out of operation. Hence, the thermal valve may be completely removed from the system for repair or replacement without rendering the system inoperative as a refrigeration mechanism or as a mechanism that may be defrosted.

Theparts of the distributor mechanism are very easily assembled. It is necessary only to insert a gasket at the left of the opening 36, and then push the insert block to in place thereagainst, observing that it is necessary to align the pin 48 with its opening in the housing 33 in order to'get the proper fit, or location, of the insert 42. The valve 60 is then slid over the outside of the sleeve 55 and its spring located in proper position. Thereupon, the head 31, with the valve 55 threaded thereinto but withdrawn so that it will not seat against the seat in the insert, is bolted onto the housing 33. The packing gland 51 is tightened by the plug 58. The valve 56 may then be moved to the desired position and the cap 59 applied over the head of the valve to insure positive sealing against leakage of the gland.

What is claimed is:

1. In a refrigeration mechanism, a refrigerant conducting housing having refrigerant passage means therethrough comprising an inlet and an outlet and pressure-reducing means between the inlet and the outlet, a second inlet into the housing, a port from the second inlet to the outlet, a valve for said port, means normally yieldably holding the valve in position closing the port to prevent communication between the second inlet and the outlet, piston means connected to the valve and responsive to pressure in the second inlet to open the valve upon existence of predetermined pressure in the second inlet, and means connecting the opposite side of the piston to the first inlet through the pressure reducing means whereby pressure from the first inlet cooperates with the yieldable means to urge the valve closed.

2. In a refrigeration mechanism, a refrigerant conducting housing having refrigerant passage means therethrough comprising an inlet and a first outlet and pressure-reducing means between the inlet and the outlet, a second inlet into the housing, a port from the second inlet to the outlet, a valve for said port, means normally yieldably holding the valve in position closing the port to prevent communication between the second inlet and the outlet, piston means connected to the valve and responsive to pressure in the second inlet to open the valve upon existence of predetermined pressure in the second inlet, and a third inlet into the housing communicating with the passage means to provide a connection between the third inlet and the outlet when the first and second inlets are closed from the outlet.

3. In a refrigeration mechanism, a refrigerant conducting housing having refrigerant passage means therethrough comprising an inlet and an outlet and pressure-reducing means between the inlet and the outlet, a second inlet into the housing, a port from the second inlet to the outlet, a valve for said port, means normally yieldably holding the valve in position closing the port to prevent communication between the second inlet and the outlet, piston means connected to the valve and responsive to pressure in the second inlet to open the valve upon existence of predetermined pressure in the second inlet, a third inlet into the housing, communicating with the passage means, and a valve in the housing operable to cut oif the flow between the first inlet and the outlet and the third inlet.

4. In a refrigeration mechanism, a distributor housing having an inlet, a well therein connected with the inlet, a distribution insert in the well, said insert having a head and a sleeve portion extending from the head, the sleeve portion being smaller than the head and providing an outer space in the well, a port in the head registering with the inlet, an enlarged bore extending through the sleeve and meeting the port to form a valve seat, a plurality of outlet passages radiating from the bore, a plurality of transverse passages leading the outlet passages through the head to communicate with the outer space provided by the sleeve, a valve slidable on the sleeve to close said transverse passages, means normally urging the valve closed, piston means on the valve providing a pressure chamber within the outer space provided by the sleeve, a second fluid inlet leading to the pressure chamber whereby fluid pressure may act on said piston to open the valve, a valve within said enlarged bore and movable against said valve seat to close off the distribution inlet, and means to close the well and the end of the sleeve.

5. In a refrigeration mechanism, a distributor housing having an inlet, a well therein connected with the inlet, a distribution insert in the well, said insert having a head and a sleeve portion extending from the head, the sleeve portion being smaller than the head and providing an outer space in the well, a port in the head registering with the inlet, an enlarged bore extending through the sleeve and meeting the port to form a valve seat, a plurality of outlet passages radiating from the bore, a plurality of transverse passages leading the outlet passages through the head to communicate with the outer space provided by the sleeve, a valve slidable on the sleeve to close said transverse passages, means normally urging the valve closed, piston means on the valve providing a pressure chamber within the outer space provided by the sleeve, a second fluid inlet leading to the pressure chamber whereby fiuid pressure may act on said piston to open the valve, a valve within said enlarged bore and movable against said valve seat to close off the distribution inlet, and means to close the Well and the end of the sleeve, a third inlet into the housing beyond the valve seat, connected with the enlarged bore in the sleeve.

6. In a refrigeration mechanism, a distributor housing having an inlet, a well therein connected with the inlet, a distribution insert in the well, said insert having a head and a sleeve portion extending from the head, the sleeve portion being smaller than the head and providing an outer space in the well, a port in the head registering with the inlet, an enlarged bore extending through the sleeve and meeting the port to form a valve seat, a plurality of outlet passages radiating from the bore, a plurality of transverse passages leading the outlet passages through the head to communicate with the outer space provided by the sleeve, a valve slidable on the sleeve to close said transverse passages, means normally urging the valve closed, piston means on the valve providing a pressure chamber Within the outer space provided by the sleeve, a second fluid inlet leading to the pressure chamber whereby fluid pressure may act on said piston to open the valve, a valve within said enlarged bore and movable against said valve seat to close off the distribution inlet, means to close the well and the end of the sleeve, said piston means on the valve being open-n its other side to the enlarged bore, and a third inlet connected with the enlarged bore.

7. In a refrigeration system, an evaporator, a

' suction line therefrom, a hot gas line, a condenser, an expansion valve, first connections from the hot gas line through the condenser and expansion valve to the evaporator, second bypass connections from the hot gas line to the evaporator, compressor means to force the hot gas through the first connections or through the bypass connections, and valve means for causing the compressor to force the hot gas through the bypass connections, said valve means including valve apparatus to close the first connections on both sides of the expansion valve for isolating it.

8. In a refrigeration system, a hot gas line, an evaporator, first connections from the hot gas line to the evaporator including a condenser and expansion valve, second bypass connection from the hot gas line to the evaporator, valve means at the evaporator to control flow from the bypass connections into the evaporator, biasing means yieldingly urging the valve means closed, pressure-responsive actuating means for the valve means, the actuating means being subjected on one side to hot gas pressure to open the valve means, and opposite connections whereby the actuating means is oppositely subjected to outlet pressure subsequent to the valve means, the valve means being adapted to reduce the pressure, whereby hot gas pressure may cause the actuating means to open the valve means, said opposite connections for the actuating means being also connected to the outlet side of said expansion valve in the first connections, and valve means to close the first connections.

9. In a refrigeration system, a hot gas line, an evaporator, a distributor at the inlet of the evaporator, first connections from the hot gas line to the distributor including a condenser and an expansion valve, bypass connections from the hot gas line to the distributor, and valve means in the distributor to selectively connect the first connections or the bypass connections into the evaporator.

10. In a refrigeration system, a hot gas line, an evaporator, a distributor at the inlet of the evaporator, first connections from the hot gas line to the distributor including a condenser and an expansion valve, bypass connections from the hot gas line to the distributor, and valve means in the distributor to selectively connect the first connections or the bypass connections into the evaporator, said valve means including a bypass valve and means responsive to pressure of the hot gas in the bypass line to open the bypass valve and admit hot gas to the evaporator.

,11. In a valve mechanism, a valve body having an inlet and an outlet, a valve between the inlet and the outlet, a movable pressure-responsive wall connected to the valve for operating the valve, the wall being connected on one side to the inlet, and constricting passage means between the other side of the wall and the outlet to produce reduced pressure on said other side when 'fiuid flows from the inlet through the outlet, and

another inlet into the body connecting through the constricting passage means to the outlet and to said other side of the Wall.

12. In a valve mechanism, a valve body having an inlet and an outlet, a valve between the inlet and the outlet, a movable pressure-responsive wall connected to the valve for operating the valve, the wall being connected on one side to the inlet, and constricting passage means between the other side of the wall and the outlet to produce reduced pressure on said other side when fluid flows from the inlet through the outlet, and another inlet into the body connecting through the constricting passage means to the outlet and to said other side of the wall, and another valve in the valve body for regulating flow between said other inlet and constricting passage means to the outlet.

13. In a refrigeration system, an evaporator; a condenser and an expansion valve; 21. hot gas line; a distributor housing containing an outlet and first and second inlets, the outlet being connected to the evaporator; valve means in the distributor housing between the second inlet and the outlet and movable between an open and a closed position; pressure responsive means for actuating said valve means; yieldable means biasing the valve means toward the closed position; a main connection from the first inlet to the hot gas line through the condenser and the expansion valve; a bypass connection from the second inlet to the hot gas line; one side of the pressure responsive means being connected to the second inlet and the other side of the pressure responsive means being connected to the first inlet; valve means for closing the first inlet; and a valve in the bypass line at a point removed from the distributor housing whereby when said valve is opened to admit gas into the bypass connection, the valve means in the distributor housing will automatically open to connect the second inlet with the outlet, when the first inlet is closed.

14. In a refrigeration system, an evaporator; a condenser and an expansion valve; 2, hot gas line; a distributor housing containing an outlet and first and second inlets, the outlet being connected to the evaporator; valve means in the distributor housing between the second inlet and the outlet and movable between an open and a closed position; pressure responsive means for actuating said valve means; yieldable means biasing the valve means toward the closed position; a main connection from the first inlet to the hot gas line through the condenser and the expansion valve; a bypass connection from the second inlet to the hot gas line; one side of the pressure responsive means being connected to the second inlet and the other side of the pressure responsive means being connected to the first inlet; whereby the valve means in the distributor housing will open to connect the second inlet with the outlet when the pressure in the bypass connection exceeds the pressure at the first inlet by a predetermined amount.

15. In a refrigerator mechanism, a refrigerant conducting housing; a first fluid inlet thereto; an outlet therefrom; a second fluid inlet thereto; port means between the second inlet and the outlet; a first valve controlling flow through the port means; movable surface means responsive to fluid pressure in the second inlet to open the first valve; and second valve means between the first inlet and the outlet for varying the fiow between subjected to the pressure from the first inlet when the second valve is open tending to urge the first valve toward the closed position;

FRANKLIN M. MecDOUGALL.

REFERENCES CI'EED The following references are bflIBCOld in the file of this patent:

UNITED STATES PAI'ENTS Number Gulick July 15, 1924 Number mb r Name Date Hilger Sept. 28, 1926 Coles July 9, 1929 Oliphant Apr. 8, 1930 Warren Oct. 13, 1931 Ruppricht Aug. 4, 1936 Warren Aug. 30, 1938 Newton Dec. 30, 1947 Lund Oct. 19, 1948 FOREIGN PATENTS Country Date Germany 1881 Italy e Jan. 25, 1928 

